—- SVENSKA
KRAFTNÄT
T
SWEDISH NATIONAL GRID
UNIT, BUSI NESS AREA
AFL, Asset Management Lines
DATE
2016-06-09
OUR REFERENCE
TR05-11E
C O N S IkJJLLTT,A T I O N S
må(J
REVISION
3
T E C H N I C A L G UI D E L I N E
APPROVED
Td
Overhead transmission lines
Insulators
Introduction
These guidelines describe the requirements on insulators for insulator sets in accordance with TR 05-10E for overhead transmission lines with alternating current and
cover design and inspection. The guidelines intend to guarantee satisfactory performance of insulators during the lifetime of the overhead line and shall be used at purchasing of insulators.
This English text is to be regarded as a translation of the Swedish guideline. The Swedish text and the interpretation thereof shall govern the contract and the legal rela­
tions between parties.
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Notes
Change notes
Date
1 (A)
New template.
09 / 07 / 2008
2
New template. Clause 11.5.2.1 and 11.5.2.3 revised. Clausel 11.9.2.5
revised. Rev. 11.9.2.7.
02 / 04 / 2012
3
New template clause numbers changed. Clause 5.1.6 inserted. Clause 09 / 06 / 2016
7.1 sample size revised.
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Content
1
References .................................................................................................................6
2
Scope .......................................................................................................................... 7
3
Definition ................................................................................................................... 7
4
Description ................................................................................................................ 7
4.1
5
Ball and socket type disc insulator ............................................................. 7
Requirements ............................................................................................................ 7
5.1
5.2
5.3
General ......................................................................................................... 7
5.1.1
Material ........................................................................................ 8
5.1.2
Insulating part ............................................................................. 8
5.1.3
Couplings ...................................................................................... 8
5.1.4
Cement .......................................................................................... 8
5.1.5
Locking devices............................................................................. 8
5.1.6
Fog type disc insulator corrosion protection ............................. 8
Design .......................................................................................................... 8
5.2.1
Measurement ................................................................................ 8
5.2.2
Displacements .............................................................................. 8
5.2.3
Couplings ...................................................................................... 8
5.2.4
Locking devices............................................................................. 8
5.2.5
Porosity ......................................................................................... 8
5.2.6
Zinc layer ...................................................................................... 8
Mechanical requirements ............................................................................9
5.3.1
Locking system ..............................................................................9
5.3.2
Electromechanical failing load ....................................................9
5.3.3
Mechanical failing load ................................................................9
5.3.4
Temperature cycling .....................................................................9
5.3.5
Thermal shock ...............................................................................9
5.3.6
Thermal-mechanical failing load.................................................9
5.3.7
Residual failing load .....................................................................9
5.3.8
Impact properties ..........................................................................9
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5.3.9
5.4
6
7
Routine test load ............................................................................9
Electrical requirements ...............................................................................9
5.4.1
Dry lightning impulse withstand voltage test ............................9
5.4.2
Wet power frequency withstand voltage test..............................9
5.4.3
Power frequency puncture voltage ............................................ 10
5.4.4
Flash over at fast front over-voltages ....................................... 10
5.4.5
Radio interference ....................................................................... 10
Type test ................................................................................................................... 10
6.1
General ....................................................................................................... 10
6.2
Dimensions ................................................................................................. 10
6.3
Displacements ............................................................................................ 10
6.4
Locking system ........................................................................................... 10
6.5
Radio interference ..................................................................................... 10
6.6
Temperature cycling.................................................................................. 11
6.7
Electromechanical failing load ................................................................. 11
6.8
Mechanical failing load ............................................................................. 11
6.9
Porosity ....................................................................................................... 11
6.10
Thickness of zinc coating ........................................................................... 12
6.11
Dry lightning impulse withstand voltage test. ........................................ 12
6.12
Wet power frequency withstand voltage test .......................................... 12
6.13
Thermal shock ............................................................................................ 12
6.14
Power frequency puncture voltage........................................................... 12
6.15
Impact properties ...................................................................................... 12
6.16
Thermal-mechanical performance ........................................................... 12
6.17
Residual strength ....................................................................................... 12
Sample test .............................................................................................................. 13
7.1
General ....................................................................................................... 13
7.2
Dimensions ................................................................................................. 14
7.3
Displacements ............................................................................................ 14
7.4
Locking system ........................................................................................... 14
7.5
Temperature cycling.................................................................................. 14
7.6
Electromechanical failing load ................................................................. 14
7.7
Mechanical failing load ............................................................................. 14
7.8
Thermal shock ............................................................................................ 14
7.9
Power frequency puncture voltage........................................................... 15
7.10
Porosity ....................................................................................................... 15
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8
9
7.11
Thickness of zinc coating ........................................................................... 15
7.12
Residual strength ....................................................................................... 15
Routine tests ............................................................................................................ 15
8.1
Visual inspection ........................................................................................ 15
8.2
Routine test load ........................................................................................ 15
8.3
Electrical test .............................................................................................. 15
Delivery .................................................................................................................... 16
9.1
General ....................................................................................................... 16
9.2
Documentation ........................................................................................... 16
9.3
10
9.2.1
Assembly drawing ...................................................................... 16
9.2.2
List of material ............................................................................ 16
9.2.3
Manufacturing process ............................................................... 16
9.2.4
Quality system ............................................................................. 17
9.2.5
Installation instructions ............................................................. 17
9.2.6
Reports ......................................................................................... 17
Transport and storing ............................................................................... 17
Tables ....................................................................................................................... 18
Table 1A
Fog type disc insulators, dimensions (Older type of
insulator) .................................................................................................... 18
Table 1B
Fog type disc insulators, dimensions ......................................... 18
Table 2 Disc insulators, Electrical and Mechanical Requirements ..................... 19
Table 3 Disc insulators, Type test ......................................................................... 20
11
Figures ..................................................................................................................... 21
Figure 1
Disc insulator............................................................................... 21
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1
References
Note that standards, regulations etc. which are referred to in these guidelines are subject to continuous change and can be withdrawn, revised or replaced. It is the obligation that the contractor immediately will inform the client of such changes.
C.I.S.P.R 16-2-1
Specification for radio disturbance and immunity
measuring apparatus and methods - Part 2: Methods of
measurement of disturbances and immunity
IEC/TR0 60797
Residual strength of string insulator units of glass or
ceramic material for overhead lines after mechanical
damage of the dielectric
SS-EN 10045-1
Metallic materials - Charpy impact test - Part 1:Test
method
SS-EN 60305
Insulators for overhead lines with a nominal voltage
above 1 kV - Ceramic or glass insulator units for a.c.
systems - Characteristics of insulator units of the cap
and pin type
SS-EN 60372
Locking devices for ball and socket couplings of string
insulator units - Dimensions and tests
SS-EN 60383-1
Insulators for overhead lines with a nominal voltage
above 1 000 V- Part 1: Ceramic or glass insulator units
for a.c. systems - Definitions, test methods and
acceptance criteria
SS-EN 60383-2
Insulators for overhead lines with a nominal voltage
above 1 000 V- Part 2: Insulator strings and insulator
sets for a.c. systems - Definitions, test methods and
acceptance criteria
SS-EN 60437
Radio interference test on high-voltage insulators
SS-EN ISO 9001
Quality management systems - Requirements
SS IEC 60120
Dimensions of ball and socket couplings of string
insulator units
SS-ISO 5455
Technical drawings - Scales
SvK TR 05-10
Technical guidelines – Insulator sets
SvK TR 08
Technical guidelines - Documentation
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2
Scope
These guidelines describe the requirements on insulators for insulator sets in accordance with TR 05-10E for overhead transmission lines with alternating current and
cover design and inspection.
The guidelines intend to guarantee satisfactory performance of insulators during the
lifetime of the overhead line and shall be used at purchasing of insulators.
3
Definition
Technical terms and definitions used in these guidelines:
Residual breaking load
Breaking load of insulators with the shed of the insulating part cracked or completely
broken off.
4
Description
4.1
Ball and socket type disc insulator
Individual insulators with the insulating part shaped as a dish made from porcelain or
glass with sockets shaped as into a cap and a pin with an end ball made from metal.
See SS-EN 60305.
5
Requirements
5.1
General
Insulators shall be able to withstand the mechanical stresses which can occur during
transport, handling and installation at temperatures as low as –40 °C, in addition to
the mechanical stresses which can occur during the lifetime of the overhead line at
temperatures from -50 °C to +100 °C.
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5.1.1
Material
5.1.2
Insulating part
Disc insulators shall have insulating parts made from toughened glass.
5.1.3
Couplings
Caps with sockets shall be made from malleable cast iron, spheroidal graphite iron or
forged steel and be hot dip galvanised.
Pins with end balls shall be made from forged steel and be hot dip galvanised.
5.1.4
Cement
Cement for assembling shall be aluminous cement.
5.1.5
Locking devices
Locking devices shall be made from bronze, copper alloy with not more than 15 % zinc
content or austenitic stainless steel.
5.1.6
Fog type disc insulator corrosion protection
Fog type disc insulator shall be equipped with a corrosion protection zinc sleeve.
5.2
Design
5.2.1
Measurement
Disc insulators with normal creepage distances shall have measurements in accordance with SS-EN 60305.
Disc insulators with extended creepage distances shall have measurements in accordance with Table 1.
5.2.2 Displacements
The maximum axial and radial displacement shall conform to SS-EN 60383-1.
5.2.3 Couplings
Balls and sockets shall conform to SS-IEC 60120. However size 16B shall not be used.
5.2.4 Locking devices
Locking devices shall conform to SS-EN 60372. However W-clips are not to be used
5.2.5 Porosity
Porcelain porosity shall conform to the requirements of SS-EN 60383-1.
5.2.6 Zinc layer
The thickness of the zinc layer shall conform to the requirements of SS-EN 60383-1.
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5.3
Mechanical requirements
5.3.1
Locking system
The locking system shall conform to the requirements of SS-EN 60372.
5.3.2 Electromechanical failing load
Insulators made from porcelain shall conform to the electromechanical failing load
requirements of SS-EN 60305, see Table 2.
5.3.3 Mechanical failing load
Insulators made from toughened glass shall conform to the mechanical failing load
requirements of SS-EN 60305, see Table 2.
5.3.4 Temperature cycling
Insulators made from porcelain shall conform to the temperature cycling requirements
of SS-EN 60383-1.
5.3.5 Thermal shock
Insulators made from toughened glass shall conform to the requirements for thermal
shock in accordance with SS-EN 60383-1.
5.3.6 Thermal-mechanical failing load
Insulators shall conform to the thermal-mechanical performance requirements of SSEN 60383-1, see Table 2.
5.3.7 Residual failing load
Insulators shall conform to the residual failing load requirements of Table 2.
5.3.8 Impact properties
Insulator pins shall conform to the impact property requirements of Table 2.
5.3.9 Routine test load
Insulators shall conform to the routine test load requirements of Table 2.
5.4
Electrical requirements
5.4.1
Dry lightning impulse withstand voltage test
Insulators made from toughened glass or porcelain shall conform to the dry lightning
impulse withstand voltage requirements of Table 2.
5.4.2 Wet power frequency withstand voltage test
Insulators made from toughened glass or porcelain shall conform to the wet power
frequency withstand voltage requirements of Table 2.
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5.4.3 Power frequency puncture voltage
Insulators made from toughened glass or porcelain shall conform to the power frequency puncture voltage requirements of Table 2.
5.4.4 Flash over at fast front over-voltages
Insulators shall conform to the flashover requirements with fast front over-voltages.
5.4.5 Radio interference
The radio interference level for insulators shall be determined at 20 kV respectively 24
kV 50 Hz alternating current (r.m.s. value) over 1 µV interference voltage and 500 kHz
measuring frequency. The radio interference level shall comply with the requirements
of acceptance level C20 ≥ 1,6 at 20 kV respectively C24 ≥ 1,2 at 24 kV.
6
Type test
6.1
General
Unless otherwise agreed type tests shall be performed in accordance with Clauses 6.26.17 on the number of samples as given in Tables 3.
The tests shall be performed in such a way that neither the method nor the equipment
affects the result.
6.2
Dimensions
The number of insulators to be tested is given in Table 3.
The tests shall be performed on disc insulators according to SS-EN 60383-1.
6.3
Displacements
The number of insulators to be tested is given in Table 3.
For disc insulators the tests shall be performed in accordance with SS-EN 60383-1.
6.4
Locking system
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1.
6.5
Radio interference
The number of insulators to be tested is given in Table 3.
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The test shall, on cap & pin insulators, be performed with 20 kV respectively 24 kV 50
Hz alternating current (r.m.s. value) over 1 µV interference voltage and 500 kHz
measuring frequency at test in accordance with C.I.S.P.R 16-2-1 and SS-EN 60437.
From the individual interference levels X measured at the test shall the mean value X
and the standard deviation σn-1 be calculated.
where
X20 = mean value of the lot at 20 kV [dB]
X24 = mean value of the lot at 24 kV [dB]
σ20 = standard deviation of the lot at 20 kV [dB]
σ24 = standard deviation of the lot at 24 kV [dB]
C20 = acceptance level at 20 kV
C24 = acceptance level at 24 kV
The insulators is considered to meet the requirements if: X20 ≤ 60 – 1,6σ20 and X24 ≤
60 – 1,2σ24.
6.6
Temperature cycling
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1 for insulators made
from porcelain.
6.7
Electromechanical failing load
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from porcelain.
6.8
Mechanical failing load
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from glass.
6.9
Porosity
The number of insulators to be tested is given in Table 3.
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The tests shall be performed in accordance with SS-EN 60383-1 for insulators made
from porcelain.
6.10 Thickness of zinc coating
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1.
6.11 Dry lightning impulse withstand voltage test.
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-2 on an assembled insulator string consisting of 5 disc insulators or alternatively one composite insulator.
6.12 Wet power frequency withstand voltage test
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-2 on an assembled insulator string consisting of 5 disc insulators or alternatively one composite insulator.
6.13 Thermal shock
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from toughened glass.
6.14 Power frequency puncture voltage
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators.
6.15 Impact properties
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 10045-1.
6.16 Thermal-mechanical performance
The number of insulators to be tested is given in Table 3.
The tests shall be performed in accordance with SS-EN 60383-1.
6.17 Residual strength
The number of insulators to be tested is given in Table 3.
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The tests shall be performed in accordance with IEC/TR0 60797 for disc insulators.
7
Sample test
7.1
General
Sample tests shall be carried out by the manufacturer on insulators selected at random
from the lot to be supplied.
Test samples shall be supplied by the manufacturer free of charge to the client and
shall not be included in the lot to be supplied.
The size of the test samples are indicated in table below.
Lot size
Sample size
N≤
300
1-3 subject to agreement
300
<N≤
2000
4
2000
<N≤
5000
8
5000
<N≤
10000
12
The sample shall be subject to testing in accordance with Clauses 7.2-7.12 inclusive.
Insulators which have been submitted to test shall be discarded.
The manufacturer shall inform the client when sample tests will be performed.
Records from the sample tests shall be filed by the manufacturer and be shown to the
client on request. In the case where any component does not comply with the requirements, re-testing shall be performed as below.
If only one insulator, or part thereof, fails to comply with the sample test requirement,
a new sample equal to twice the quantity originally submitted for that test shall be
subject to re-testing. The re-testing shall comprise the test or tests in which failure
occurred.
If two or more insulators, or parts thereof, fail to comply with any of the sample tests,
or if any failure occurs during re-testing, the complete lot shall be considered not to
comply with the requirements.
Provided that the cause of the failure can be clearly identified, the manufacturer may
sort the lot to eliminate all the insulators with this defect. The sorted lot shall then be
resubmitted for sample testing. The number then selected shall be three times the first
quantity chosen for the test. The re-testing shall comprise the test or tests in which
failure occurred in the original test.
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If any insulator, or part there-of of the sorted lot, fails during this re-testing, the complete lot shall be considered as not complying with the requirements.
7.2
Dimensions
Number of insulators to be tested: E1 & E2.
The tests shall be performed in accordance with SS-EN 60383-1.
7.3
Displacements
Numbers of insulators to be tested: E1 & E2.
The tests shall be performed on disc insulators in accordance with SS-EN 60383-1.
7.4
Locking system
Numbers of insulators to be tested: E1 & E2.
The tests shall be performed in accordance with SS-EN 60383-1.
7.5
Temperature cycling
Numbers of insulators to be tested: E1 & E2.
The tests shall be performed in accordance with SS-EN 60383-1 for insulators made
from porcelain.
7.6
Electromechanical failing load
Number of insulators to be tested: E1.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from porcelain.
7.7
Mechanical failing load
Number of insulators to be tested: E1.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from glass.
7.8
Thermal shock
Number of insulators to be tested: E2.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from toughened glass.
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7.9
Power frequency puncture voltage
Number of insulators to be tested: E2.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators.
7.10 Porosity
Number of insulators to be tested: E1.
The tests shall be performed in accordance with SS-EN 60383-1 for insulators made
from porcelain.
7.11 Thickness of zinc coating
Number of insulators to be tested: E2.
The tests shall be performed in accordance with SS-EN 60383-1.
7.12 Residual strength
Number of insulators to be tested: E3.
The tests shall be performed in accordance with IEC/TR0 60797 for disc insulators.
8
Routine tests
8.1
Visual inspection
All insulators shall be visually inspected.
The visual inspection shall be performed in accordance with SS-EN 60383-1 for disc
insulators.
8.2
Routine test load
All insulators shall be tested.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators.
8.3
Electrical test
All insulators shall be tested.
The tests shall be performed in accordance with SS-EN 60383-1 for disc insulators
made from porcelain.
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9
Delivery
9.1
General
The client shall, according to these guidelines, approve the insulators before delivery.
For approval the manufacturer shall demonstrate that the insulators conform to these
guidelines.
The manufacturer shall provide documentation in accordance with Clauses 9.2.1 9.2.6 for approval.
The approval of drawings by the client does not release the manufacturer from his
obligations regarding the insulators complying with these guidelines.
All documentation shall be written in Swedish or English.
9.2
Documentation
General requirements for documentation see SvK TR 08E.
9.2.1 Assembly drawing
The assembly drawing shall have a minimum of two views at an appropriate scale in
accordance with SS-ISO 5455. On the drawing shall be given:
•
Type and/or Catalogue number
•
Principal dimensions
•
Failing load
•
Electrical data
•
Creepage distance
•
All marking
•
Weight
•
List of materials
9.2.2 List of material
Description of material in included parts.
9.2.3 Manufacturing process
Description of the manufacturing process
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9.2.4 Quality system
Quality system in accordance with SS-EN ISO 9001.
9.2.5 Installation instructions
Installation instructions in Swedish or English with the required drawings.
9.2.6 Reports
Report in accordance with Clause 6 Type test report, 7 Sample test report and 8 Routine tests report.
9.3
Transport and storing
The insulators shall be packed up in that way that they will not be damaged or fouled
at transport, construction and at storing.
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10
Tables
Table 1A Fog type disc insulators, dimensions
(Older type of insulator)
Designation
U70fog
U120fog
U210fog
U300fog
Max. nominal diameter of insulator disc
mm
255
255
320
400
Nominal coupling length
mm
146
146
170
195
Min. nominal creepage distance
mm
430
430
550
690
Max. pin/ball length1)
mm
30
30
35
45
*
16A
16A
20
24
Size of coupling IEC 60120
Table 1B Fog type disc insulators, dimensions
Designation according to
IEC 60305
U70BLP
U120BP
U210BP
U300BP
Max. nominal diameter of
insulator disc
mm
280
280
330
400
Nominal coupling length
mm
146
146
170
195
Min. nominal creepage distance
mm
440
440
525
590
Max. pin/ball length1)
mm
30
30
35
45
*
16A
16A
20
24
Size of coupling IEC 60120
1) Maximum vertical distance from the lower edge of the ball to the lowest part of the
insulator disc.
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Table 2 Disc insulators, Electrical and Mechanical Requirements
Designation
U70
U120
U210
U300
U70fog
U120fog
U210fo
g
U300fo
g
Designation
according to
IEC 60305
U70BL
U120B
U210B
U300B
U70BLP
U120BP
U210B
P
U300B
P
Electromechanical
failing load
kN
70
120
210
300
70
120
210
300
Mechanical failing
load
kN
70
120
210
300
70
120
210
300
Thermalmechanical failing
load
kN
70
120
210
300
70
120
210
300
Residual failing
load
kN
45,5
78
136,5
195
45,5
78
136,5
195
Routine test load
kN
35
60
105
150
35
60
105
150
Dry impulse
withstand voltage
kV
400
400
455
500
400
400
480
525
Wet power frequency withstand
voltage 1)
kV
170
170
195
215
170
170
205
220
Power frequency
puncture voltage
kV
110
110
125
130
130
130
140
140
Impact properties
at 0°C
J
27
27
27
27
27
27
27
27
1)
1) To be tested on a short insulator string comprising 5 insulator units.
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Table 3 Disc insulators, Type test
Type of test
Verification of dimensions
Gauging of socket
Items to be tested
Porcelain
Glass
Size
Number
Size
Number
15
15
1-15
1-15
Gauging of ball
1-15
1-15
Insulator diameter
11-15
11-15
Spacing
11-15
11-15
Creepage distance
11-15
11-15
Verification of displacements
Axial run-out
15
1-15
15
1-15
Radial run-out
15
1-15
15
1-15
5
11-15
5
11-15
Radio interference
10
1-10
10
1-10
Temperature cycling
10
1-10
*
*
Electromechanical failing load
10
1-10
*
*
Mechanical failing load
*
*
10
1-10
Porosity
10
1-10
*
*
Thickness of zinc coating
5
11-15
5
11-15
Dry lightning impulse withstand
voltage test
1ss1)
11-15
1ss1)
11-15
Wet power frequency withstand
voltage test
1ss1)
11-15
1ss1)
11-15
Thermal shock
*
*
5
11-15
Power frequency puncture voltage
5
11-15
5
11-15
Flash over at fast front overvoltages
5
11-15
5
11-15
Ball pin impact properties
5
11-15
5
11-15
Thermal-mechanical performance
Residual strength
10
25
16-25
26-50
10
25
16-25
26-50
Verification of the locking system
Measurement
Hardness
Resistance to bending
Corrosion resistance
1) Refers to a short string consisting of 5 insulator units.
TEKNISK RIKTLINJE
2016-06-09
TR05-11E
20 (21)
11
Figures
Figure 1
Disc insulator
TEKNISK RIKTLINJE
2016-06-09
TR05-11E
21 (21)